Re: (forw) Bug#298060: Please don't install login as setuid root

[Samuel Thibault <samuel.thibault@labri.fr>]

Wouter Verhelst, le mar 08 mar 2005 17:03:11 +0100, a dit :
> Op za, 05-03-2005 te 22:56 -0800, schreef Matt Zimmerman:
> > On Sat, Mar 05, 2005 at 03:34:58PM +0100, Christian Perrier wrote:
> > 
> > > Security and release teams, may I have your advice about this suggestion?
> > > 
> > > As you may know, I currently act as maintainer for the shadow package,
> > > but I'm also aware of my own weaknesses when it comes at security (and
> > > security-related) issues so I prefer getting the advice of more
> > > competent people.
> > > 
> > > Given that installing login non setuid has been blessed for Ubuntu,
> > > I'm inclined to follow the suggestion, but doing so close to a release
> > > is maybe not wise.....so I'm seeking for advices..:-)
> > 
> > FWIW, We've been doing this for some time in Ubuntu, and no one has missed
> > it.  In this age of pseudoterminals and single-user systems...
> 
> On Linux.
> 
> I'm not exactly sure about this, but I think it might break the way the
> Hurd does a login. On The Hurd, you don't get a login prompt; rather,
> you get a login /shell/ which allows you to do some things without
> having been logged on; loggin in then requires you to do 'login <user>'.
> It /might/ be the case that this requires /bin/login to be setuid root,
> but I'm not sure. Hurd developers (Cc'ed), care to shed some light here?

It does even *less* need to be setuid root: login way be run without
*any* identity: it gets uid from the passwd server in exchange of the
correct password for the uid. No need to be root for that.

Regards,
Samuel Thibault